GI 4 Flashcards
Feed pattern: gastric motor⛔️ control
Full Duodenum: ⬇️emptying= allow Time for neutralize/digestion
Neural- enterogastric long reflex: OPS
osm/pH/strectch-receptors✳️SNS
Hormonal- AA/fat✳️CCK: compete with Gastrin & CHO✳️incretins (GLP)
Feed pattern: gastric motor ✳️control
Full stomach:⬆motility&️emptying
Neural activity- aff mechano&chemoR (AA/pH/osm)➡️GVA➡️ vagus reflex:PSNS ✳️ENS effectors
Hormonal- Ach/GRP neurons/AA/ alk pH➡️✳️GASTRIN rel
Feed pattern: gastric emptying rate
Emptying ➰ diet type
CHO>protein>fat
Fasting pattern: gastric MMC
- Slow waves propagate entire length ⛔️contractions
- Int. Spikes
- Spike at each slow wave=peristalsis
✳️pylorus open
Gastric juice
HCl H2O Pepsin IF (B12) Mucus
Gastric HCl fn
PODBD
✳️pesinogen Optimal pH 2-4 Denatures protein➡️AA Bacteriocidal Demineralize bone
HCl secr: parietal cell
HK-ATPase: active transport➡️H+ out
Cl-:HCO3- exchanger BL mem➡️Cl in
➡️➡️Cl- out at Apical surface
BL Mem: NaHCO3 ➡️alk tide in blood
Histamine secr
Gastrin/Ach➡️✳️ECL: histamine secr ➡️ H2-Rec:Parietal cell ⬆️cAMP✳️HK-ATPase
Somatostatin ⛔️ECL
H2 blocker Zantac & famotidine
Ach:mAch
mAch: ⬆️ Ca2+ ➡️✳️HK-ATPase (ST)
✳️G Cell & Ecl: histamine rel➡️✳️gastrin
Gastrin
Ach:mAch/GRP/AA/alk➡️ ✳️G cells ➡️ gastrin rel:CCKB-R parietal cell➡️✳️HK-ATPase
Somatostatin
Acid: ✳️D cells➡️ ⛔️P/ECL/G cells
⛔️HAG
3 phase Gastric Secretion(meal✳️)
Cephalic
Gastric
Intestinal
Cephalic phase
Conditioned reflexes of appetite
Neural➡️✳️PHG
Preps gastric env for meal
Gastric phase
Neural-food in stomach➡️
✳️stretch/chemo-R➡️ENS+PSNS:
✳️Ach neurons:mAch➡️✳️PHG &GRP➡️⬆️⬆️gastrin
Hormonal- Ach/GRP/AA/food buff eff:
⬆️gastrin
Intestinal phase
⬇️gastrin:⬆️CCK=✳️sm amt GA secr
⛔️Acid Secr
Local-Somatostatin ➡️⛔️PHG
Enterogastric reflex:⬆️SNS
CCK competitive inhib
Intrinsic factor
Glycoprotein secr by parietal cell
Binds vitamin B12 ⛔️digestion➡️blood ✳️Hb & RBC production
Atrophic gastritis
Autoimm Parietal cells: ⬇️IF⬇️B12⬇️RBC& achlorhydria
Mucosal barrier 3 physio
ABC
Alk mucus barrier
Blood flow mucosa high
Cell turnover/restitution
Prostaglandins
⚡️to barrier➡️rel phospholipaseA ➡️ARA ➡️✳️COX1: “protective” PG
&✳️COX2: “pain” PG
Vomit center
Reticular formation: VVCC inputs
Vesti App
Visceral Aff
CTZ
CNS
Vomition
NRV
Nausea- salivate & rev peristalsis
Retching- relax whole stomach
Vomition- sustained contraction
Protracted vomiting
VAK
Hypovolemia
Systemic Alkalosis
Hypokalemia
